Struct bumpalo::boxed::Box

#[repr(transparent)]
pub struct Box<'a, T: ?Sized>(_);

An owned pointer to a bump-allocated T value, that runs Drop implementations.

See the module-level documentation for more details.

Implementations

impl<'a, T> Box<'a, T>

pub fn new_in(x: T, a: &'a Bump) -> Box<'a, T>

Allocates memory on the heap and then places x into it.

This doesn’t actually allocate if T is zero-sized.

Examples

use bumpalo::{Bump, boxed::Box};

let b = Bump::new();

let five = Box::new_in(5, &b);

pub fn pin_in(x: T, a: &'a Bump) -> Pin<Box<'a, T>>

Constructs a new Pin<Box<T>>. If T does not implement Unpin, then x will be pinned in memory and unable to be moved.

impl<'a, T: ?Sized> Box<'a, T>

pub unsafe fn from_raw(raw: *mut T) -> Self

Constructs a box from a raw pointer.

After calling this function, the raw pointer is owned by the resulting Box. Specifically, the Box destructor will call the destructor of T and free the allocated memory. For this to be safe, the memory must have been allocated in accordance with the memory layout used by Box .

Safety

This function is unsafe because improper use may lead to memory problems. For example, a double-free may occur if the function is called twice on the same raw pointer.

Examples

Recreate a Box which was previously converted to a raw pointer using Box::into_raw:

use bumpalo::{Bump, boxed::Box};

let b = Bump::new();

let x = Box::new_in(5, &b);
let ptr = Box::into_raw(x);
let x = unsafe { Box::from_raw(ptr) }; // Note that new `x`'s lifetime is unbound. It must be bound to the `b` immutable borrow before `b` is reset.

Manually create a Box from scratch by using the bump allocator:

use std::alloc::{alloc, Layout};
use bumpalo::{Bump, boxed::Box};

let b = Bump::new();

unsafe {
    let ptr = b.alloc_layout(Layout::new::<i32>()).as_ptr() as *mut i32;
    *ptr = 5;
    let x = Box::from_raw(ptr); // Note that `x`'s lifetime is unbound. It must be bound to the `b` immutable borrow before `b` is reset.
}

pub fn into_raw(b: Box<'a, T>) -> *mut T

Consumes the Box, returning a wrapped raw pointer.

The pointer will be properly aligned and non-null.

After calling this function, the caller is responsible for the value previously managed by the Box. In particular, the caller should properly destroy T. The easiest way to do this is to convert the raw pointer back into a Box with the Box::from_raw function, allowing the Box destructor to perform the cleanup.

Note: this is an associated function, which means that you have to call it as Box::into_raw(b) instead of b.into_raw(). This is so that there is no conflict with a method on the inner type.

Examples

Converting the raw pointer back into a Box with Box::from_raw for automatic cleanup:

use bumpalo::{Bump, boxed::Box};

let b = Bump::new();

let x = Box::new_in(String::from("Hello"), &b);
let ptr = Box::into_raw(x);
let x = unsafe { Box::from_raw(ptr) }; // Note that new `x`'s lifetime is unbound. It must be bound to the `b` immutable borrow before `b` is reset.

Manual cleanup by explicitly running the destructor:

use std::ptr;
use bumpalo::{Bump, boxed::Box};

let b = Bump::new();

let mut x = Box::new_in(String::from("Hello"), &b);
let p = Box::into_raw(x);
unsafe {
    ptr::drop_in_place(p);
}

pub fn leak(b: Box<'a, T>) -> &'a mut T

Consumes and leaks the Box, returning a mutable reference, &'a mut T. Note that the type T must outlive the chosen lifetime 'a. If the type has only static references, or none at all, then this may be chosen to be 'static.

This function is mainly useful for data that lives for the remainder of the program’s life. Dropping the returned reference will cause a memory leak. If this is not acceptable, the reference should first be wrapped with the Box::from_raw function producing a Box. This Box can then be dropped which will properly destroy T and release the allocated memory.

Note: this is an associated function, which means that you have to call it as Box::leak(b) instead of b.leak(). This is so that there is no conflict with a method on the inner type.

Examples

Simple usage:

use bumpalo::{Bump, boxed::Box};

let b = Bump::new();

let x = Box::new_in(41, &b);
let reference: &mut usize = Box::leak(x);
*reference += 1;
assert_eq!(*reference, 42);

use bumpalo::{Bump, boxed::Box, vec};

let b = Bump::new();

let x = vec![in &b; 1, 2, 3].into_boxed_slice();
let reference = Box::leak(x);
reference[0] = 4;
assert_eq!(*reference, [4, 2, 3]);

impl<'a> Box<'a, dyn Any>

pub fn downcast<T: Any>(self) -> Result<Box<'a, T>, Box<'a, dyn Any>>

Attempt to downcast the box to a concrete type.

Examples

use std::any::Any;

fn print_if_string(value: Box<dyn Any>) {
    if let Ok(string) = value.downcast::<String>() {
        println!("String ({}): {}", string.len(), string);
    }
}

let my_string = "Hello World".to_string();
print_if_string(Box::new(my_string));
print_if_string(Box::new(0i8));

impl<'a> Box<'a, dyn Any + Send>

pub fn downcast<T: Any>(self) -> Result<Box<'a, T>, Box<'a, dyn Any + Send>>

Attempt to downcast the box to a concrete type.

Examples

use std::any::Any;

fn print_if_string(value: Box<dyn Any + Send>) {
    if let Ok(string) = value.downcast::<String>() {
        println!("String ({}): {}", string.len(), string);
    }
}

let my_string = "Hello World".to_string();
print_if_string(Box::new(my_string));
print_if_string(Box::new(0i8));

impl<'a, A> Box<'a, [A]>

pub fn from_iter_in<T: IntoIterator<Item = A>>(iter: T, a: &'a Bump) -> Self

Creates a value from an iterator. This method is adapted version of FromIterator::from_iter. It cannot be made as that trait implementation given different signature.

Examples

Basic usage:

use bumpalo::{Bump, boxed::Box, vec};

let b = Bump::new();

let five_fives = std::iter::repeat(5).take(5);
let slice = Box::from_iter_in(five_fives, &b);
assert_eq!(vec![in &b; 5, 5, 5, 5, 5], &*slice);

Trait Implementations

impl<'a, T: ?Sized> AsMut<T> for Box<'a, T>

fn as_mut(&mut self) -> &mut T

Performs the conversion.

impl<'a, T: ?Sized> AsRef<T> for Box<'a, T>

fn as_ref(&self) -> &T

Performs the conversion.

impl<'a, T: ?Sized> Borrow<T> for Box<'a, T>

fn borrow(&self) -> &T

Immutably borrows from an owned value.

impl<'a, T: ?Sized> BorrowMut<T> for Box<'a, T>

fn borrow_mut(&mut self) -> &mut T

Mutably borrows from an owned value.

impl<'a, T: Debug + ?Sized> Debug for Box<'a, T>

fn fmt(&self, f: &mut Formatter<'_>) -> Result

Formats the value using the given formatter.

impl<'a, T> Default for Box<'a, [T]>

fn default() -> Box<'a, [T]>

Returns the “default value” for a type.

impl<'a> Default for Box<'a, str>

fn default() -> Box<'a, str>

Returns the “default value” for a type.

impl<'a, T: ?Sized> Deref for Box<'a, T>

type Target = T

The resulting type after dereferencing.

fn deref(&self) -> &T

Dereferences the value.

impl<'a, T: ?Sized> DerefMut for Box<'a, T>

fn deref_mut(&mut self) -> &mut T

Mutably dereferences the value.

impl<'a, T: Display + ?Sized> Display for Box<'a, T>

fn fmt(&self, f: &mut Formatter<'_>) -> Result

Formats the value using the given formatter.

impl<'a, I: DoubleEndedIterator + ?Sized> DoubleEndedIterator for Box<'a, I>

fn next_back(&mut self) -> Option<I::Item>

Removes and returns an element from the end of the iterator.

fn nth_back(&mut self, n: usize) -> Option<I::Item>

Returns the nth element from the end of the iterator.

fn advance_back_by(&mut self, n: usize) -> Result<(), usize>

🔬 This is a nightly-only experimental API. (iter_advance_by)

recently added

Advances the iterator from the back by n elements.

fn try_rfold<B, F, R>(&mut self, init: B, f: F) -> R where
    F: FnMut(B, Self::Item) -> R,
    R: Try<Output = B>, 

This is the reverse version of Iterator::try_fold(): it takes elements starting from the back of the iterator.

fn rfold<B, F>(self, init: B, f: F) -> B where
    F: FnMut(B, Self::Item) -> B, 

An iterator method that reduces the iterator’s elements to a single, final value, starting from the back.

fn rfind<P>(&mut self, predicate: P) -> Option<Self::Item> where
    P: FnMut(&Self::Item) -> bool, 

Searches for an element of an iterator from the back that satisfies a predicate.

impl<'a, T: ?Sized> Drop for Box<'a, T>

fn drop(&mut self)

Executes the destructor for this type.

impl<'a, I: ExactSizeIterator + ?Sized> ExactSizeIterator for Box<'a, I>

fn len(&self) -> usize

Returns the exact length of the iterator.

fn is_empty(&self) -> bool

🔬 This is a nightly-only experimental API. (exact_size_is_empty)

Returns true if the iterator is empty.

impl<'a, T> From<Box<'a, [T; 0]>> for Box<'a, [T]>

This impl replaces unsize coersion.

fn from(arr: Box<'a, [T; 0]>) -> Box<'a, [T]>

Performs the conversion.

impl<'a, T> From<Box<'a, [T; 1]>> for Box<'a, [T]>

This impl replaces unsize coersion.

fn from(arr: Box<'a, [T; 1]>) -> Box<'a, [T]>

Performs the conversion.

impl<'a, T> From<Box<'a, [T; 10]>> for Box<'a, [T]>

This impl replaces unsize coersion.

fn from(arr: Box<'a, [T; 10]>) -> Box<'a, [T]>

Performs the conversion.

impl<'a, T> From<Box<'a, [T; 11]>> for Box<'a, [T]>

This impl replaces unsize coersion.

fn from(arr: Box<'a, [T; 11]>) -> Box<'a, [T]>

Performs the conversion.

impl<'a, T> From<Box<'a, [T; 12]>> for Box<'a, [T]>

This impl replaces unsize coersion.

fn from(arr: Box<'a, [T; 12]>) -> Box<'a, [T]>

Performs the conversion.

impl<'a, T> From<Box<'a, [T; 13]>> for Box<'a, [T]>

This impl replaces unsize coersion.

fn from(arr: Box<'a, [T; 13]>) -> Box<'a, [T]>

Performs the conversion.

impl<'a, T> From<Box<'a, [T; 14]>> for Box<'a, [T]>

This impl replaces unsize coersion.

fn from(arr: Box<'a, [T; 14]>) -> Box<'a, [T]>

Performs the conversion.

impl<'a, T> From<Box<'a, [T; 15]>> for Box<'a, [T]>

This impl replaces unsize coersion.

fn from(arr: Box<'a, [T; 15]>) -> Box<'a, [T]>

Performs the conversion.

impl<'a, T> From<Box<'a, [T; 16]>> for Box<'a, [T]>

This impl replaces unsize coersion.

fn from(arr: Box<'a, [T; 16]>) -> Box<'a, [T]>

Performs the conversion.

impl<'a, T> From<Box<'a, [T; 17]>> for Box<'a, [T]>

This impl replaces unsize coersion.

fn from(arr: Box<'a, [T; 17]>) -> Box<'a, [T]>

Performs the conversion.

impl<'a, T> From<Box<'a, [T; 18]>> for Box<'a, [T]>

This impl replaces unsize coersion.

fn from(arr: Box<'a, [T; 18]>) -> Box<'a, [T]>

Performs the conversion.

impl<'a, T> From<Box<'a, [T; 19]>> for Box<'a, [T]>

This impl replaces unsize coersion.

fn from(arr: Box<'a, [T; 19]>) -> Box<'a, [T]>

Performs the conversion.

impl<'a, T> From<Box<'a, [T; 2]>> for Box<'a, [T]>

This impl replaces unsize coersion.

fn from(arr: Box<'a, [T; 2]>) -> Box<'a, [T]>

Performs the conversion.

impl<'a, T> From<Box<'a, [T; 20]>> for Box<'a, [T]>

This impl replaces unsize coersion.

fn from(arr: Box<'a, [T; 20]>) -> Box<'a, [T]>

Performs the conversion.

impl<'a, T> From<Box<'a, [T; 21]>> for Box<'a, [T]>

This impl replaces unsize coersion.

fn from(arr: Box<'a, [T; 21]>) -> Box<'a, [T]>

Performs the conversion.

impl<'a, T> From<Box<'a, [T; 22]>> for Box<'a, [T]>

This impl replaces unsize coersion.

fn from(arr: Box<'a, [T; 22]>) -> Box<'a, [T]>

Performs the conversion.

impl<'a, T> From<Box<'a, [T; 23]>> for Box<'a, [T]>

This impl replaces unsize coersion.

fn from(arr: Box<'a, [T; 23]>) -> Box<'a, [T]>

Performs the conversion.

impl<'a, T> From<Box<'a, [T; 24]>> for Box<'a, [T]>

This impl replaces unsize coersion.

fn from(arr: Box<'a, [T; 24]>) -> Box<'a, [T]>

Performs the conversion.

impl<'a, T> From<Box<'a, [T; 25]>> for Box<'a, [T]>

This impl replaces unsize coersion.

fn from(arr: Box<'a, [T; 25]>) -> Box<'a, [T]>

Performs the conversion.

impl<'a, T> From<Box<'a, [T; 26]>> for Box<'a, [T]>

This impl replaces unsize coersion.

fn from(arr: Box<'a, [T; 26]>) -> Box<'a, [T]>

Performs the conversion.

impl<'a, T> From<Box<'a, [T; 27]>> for Box<'a, [T]>

This impl replaces unsize coersion.

fn from(arr: Box<'a, [T; 27]>) -> Box<'a, [T]>

Performs the conversion.

impl<'a, T> From<Box<'a, [T; 28]>> for Box<'a, [T]>

This impl replaces unsize coersion.

fn from(arr: Box<'a, [T; 28]>) -> Box<'a, [T]>

Performs the conversion.

impl<'a, T> From<Box<'a, [T; 29]>> for Box<'a, [T]>

This impl replaces unsize coersion.

fn from(arr: Box<'a, [T; 29]>) -> Box<'a, [T]>

Performs the conversion.

impl<'a, T> From<Box<'a, [T; 3]>> for Box<'a, [T]>

This impl replaces unsize coersion.

fn from(arr: Box<'a, [T; 3]>) -> Box<'a, [T]>

Performs the conversion.

impl<'a, T> From<Box<'a, [T; 30]>> for Box<'a, [T]>

This impl replaces unsize coersion.

fn from(arr: Box<'a, [T; 30]>) -> Box<'a, [T]>

Performs the conversion.

impl<'a, T> From<Box<'a, [T; 31]>> for Box<'a, [T]>

This impl replaces unsize coersion.

fn from(arr: Box<'a, [T; 31]>) -> Box<'a, [T]>

Performs the conversion.

impl<'a, T> From<Box<'a, [T; 32]>> for Box<'a, [T]>

This impl replaces unsize coersion.

fn from(arr: Box<'a, [T; 32]>) -> Box<'a, [T]>

Performs the conversion.

impl<'a, T> From<Box<'a, [T; 4]>> for Box<'a, [T]>

This impl replaces unsize coersion.

fn from(arr: Box<'a, [T; 4]>) -> Box<'a, [T]>

Performs the conversion.

impl<'a, T> From<Box<'a, [T; 5]>> for Box<'a, [T]>

This impl replaces unsize coersion.

fn from(arr: Box<'a, [T; 5]>) -> Box<'a, [T]>

Performs the conversion.

impl<'a, T> From<Box<'a, [T; 6]>> for Box<'a, [T]>

This impl replaces unsize coersion.

fn from(arr: Box<'a, [T; 6]>) -> Box<'a, [T]>

Performs the conversion.

impl<'a, T> From<Box<'a, [T; 7]>> for Box<'a, [T]>

This impl replaces unsize coersion.

fn from(arr: Box<'a, [T; 7]>) -> Box<'a, [T]>

Performs the conversion.

impl<'a, T> From<Box<'a, [T; 8]>> for Box<'a, [T]>

This impl replaces unsize coersion.

fn from(arr: Box<'a, [T; 8]>) -> Box<'a, [T]>

Performs the conversion.

impl<'a, T> From<Box<'a, [T; 9]>> for Box<'a, [T]>

This impl replaces unsize coersion.

fn from(arr: Box<'a, [T; 9]>) -> Box<'a, [T]>

Performs the conversion.

impl<'bump, T: 'bump> From<Vec<'bump, T>> for Box<'bump, [T]>

fn from(v: Vec<'bump, T>) -> Box<'bump, [T]>

Performs the conversion.

impl<'a, F: ?Sized + Future + Unpin> Future for Box<'a, F>

type Output = F::Output

The type of value produced on completion.

fn poll(self: Pin<&mut Self>, cx: &mut Context<'_>) -> Poll<Self::Output>

Attempt to resolve the future to a final value, registering the current task for wakeup if the value is not yet available.

impl<'a, T: ?Sized + Hash> Hash for Box<'a, T>

fn hash<H: Hasher>(&self, state: &mut H)

Feeds this value into the given Hasher.

fn hash_slice<H>(data: &[Self], state: &mut H) where
    H: Hasher, 

Feeds a slice of this type into the given Hasher.

impl<'a, T: ?Sized + Hasher> Hasher for Box<'a, T>

fn finish(&self) -> u64

Returns the hash value for the values written so far.

fn write(&mut self, bytes: &[u8])

Writes some data into this Hasher.

fn write_u8(&mut self, i: u8)

Writes a single u8 into this hasher.

fn write_u16(&mut self, i: u16)

Writes a single u16 into this hasher.

fn write_u32(&mut self, i: u32)

Writes a single u32 into this hasher.

fn write_u64(&mut self, i: u64)

Writes a single u64 into this hasher.

fn write_u128(&mut self, i: u128)

Writes a single u128 into this hasher.

fn write_usize(&mut self, i: usize)

Writes a single usize into this hasher.

fn write_i8(&mut self, i: i8)

Writes a single i8 into this hasher.

fn write_i16(&mut self, i: i16)

Writes a single i16 into this hasher.

fn write_i32(&mut self, i: i32)

Writes a single i32 into this hasher.

fn write_i64(&mut self, i: i64)

Writes a single i64 into this hasher.

fn write_i128(&mut self, i: i128)

Writes a single i128 into this hasher.

fn write_isize(&mut self, i: isize)

Writes a single isize into this hasher.

impl<'a, I: Iterator + ?Sized> Iterator for Box<'a, I>

type Item = I::Item

The type of the elements being iterated over.

fn next(&mut self) -> Option<I::Item>

Advances the iterator and returns the next value.

fn size_hint(&self) -> (usize, Option<usize>)

Returns the bounds on the remaining length of the iterator.

fn nth(&mut self, n: usize) -> Option<I::Item>

Returns the nth element of the iterator.

fn last(self) -> Option<I::Item>

Consumes the iterator, returning the last element.

fn count(self) -> usize

Consumes the iterator, counting the number of iterations and returning it.

fn advance_by(&mut self, n: usize) -> Result<(), usize>

🔬 This is a nightly-only experimental API. (iter_advance_by)

recently added

Advances the iterator by n elements.

fn step_by(self, step: usize) -> StepBy<Self>

Creates an iterator starting at the same point, but stepping by the given amount at each iteration.

fn chain<U>(self, other: U) -> Chain<Self, <U as IntoIterator>::IntoIter> where
    U: IntoIterator<Item = Self::Item>, 

Takes two iterators and creates a new iterator over both in sequence.

fn zip<U>(self, other: U) -> Zip<Self, <U as IntoIterator>::IntoIter> where
    U: IntoIterator, 

‘Zips up’ two iterators into a single iterator of pairs.

fn intersperse(self, separator: Self::Item) -> Intersperse<Self> where
    Self::Item: Clone, 

🔬 This is a nightly-only experimental API. (iter_intersperse)

recently added

Creates a new iterator which places a copy of separator between adjacent items of the original iterator.

fn intersperse_with<G>(self, separator: G) -> IntersperseWith<Self, G> where
    G: FnMut() -> Self::Item, 

🔬 This is a nightly-only experimental API. (iter_intersperse)

recently added

Creates a new iterator which places an item generated by separator between adjacent items of the original iterator.

fn map<B, F>(self, f: F) -> Map<Self, F> where
    F: FnMut(Self::Item) -> B, 

Takes a closure and creates an iterator which calls that closure on each element.

fn for_each<F>(self, f: F) where
    F: FnMut(Self::Item), 

Calls a closure on each element of an iterator.

fn filter<P>(self, predicate: P) -> Filter<Self, P> where
    P: FnMut(&Self::Item) -> bool, 

Creates an iterator which uses a closure to determine if an element should be yielded.

fn filter_map<B, F>(self, f: F) -> FilterMap<Self, F> where
    F: FnMut(Self::Item) -> Option<B>, 

Creates an iterator that both filters and maps.

fn enumerate(self) -> Enumerate<Self>

Creates an iterator which gives the current iteration count as well as the next value.

fn peekable(self) -> Peekable<Self>

Creates an iterator which can use the peek and peek_mut methods to look at the next element of the iterator without consuming it. See their documentation for more information.

fn skip_while<P>(self, predicate: P) -> SkipWhile<Self, P> where
    P: FnMut(&Self::Item) -> bool, 

Creates an iterator that skips elements based on a predicate.

fn take_while<P>(self, predicate: P) -> TakeWhile<Self, P> where
    P: FnMut(&Self::Item) -> bool, 

Creates an iterator that yields elements based on a predicate.

fn map_while<B, P>(self, predicate: P) -> MapWhile<Self, P> where
    P: FnMut(Self::Item) -> Option<B>, 

🔬 This is a nightly-only experimental API. (iter_map_while)

recently added

Creates an iterator that both yields elements based on a predicate and maps.

fn skip(self, n: usize) -> Skip<Self>

Creates an iterator that skips the first n elements.

fn take(self, n: usize) -> Take<Self>

Creates an iterator that yields the first n elements, or fewer if the underlying iterator ends sooner.

fn scan<St, B, F>(self, initial_state: St, f: F) -> Scan<Self, St, F> where
    F: FnMut(&mut St, Self::Item) -> Option<B>, 

An iterator adaptor similar to fold that holds internal state and produces a new iterator.

fn flat_map<U, F>(self, f: F) -> FlatMap<Self, U, F> where
    F: FnMut(Self::Item) -> U,
    U: IntoIterator, 

Creates an iterator that works like map, but flattens nested structure.

fn flatten(self) -> Flatten<Self> where
    Self::Item: IntoIterator, 

Creates an iterator that flattens nested structure.

fn fuse(self) -> Fuse<Self>

Creates an iterator which ends after the first None.

fn inspect<F>(self, f: F) -> Inspect<Self, F> where
    F: FnMut(&Self::Item), 

Does something with each element of an iterator, passing the value on.

fn by_ref(&mut self) -> &mut Self

Borrows an iterator, rather than consuming it.

#[must_use = "if you really need to exhaust the iterator, consider `.for_each(drop)` instead"]

fn collect<B>(self) -> B where
    B: FromIterator<Self::Item>, 

Transforms an iterator into a collection.

fn partition<B, F>(self, f: F) -> (B, B) where
    F: FnMut(&Self::Item) -> bool,
    B: Default + Extend<Self::Item>, 

Consumes an iterator, creating two collections from it.

fn partition_in_place<'a, T, P>(self, predicate: P) -> usize where
    Self: DoubleEndedIterator<Item = &'a mut T>,
    T: 'a,
    P: FnMut(&T) -> bool, 

🔬 This is a nightly-only experimental API. (iter_partition_in_place)

new API

Reorders the elements of this iterator in-place according to the given predicate, such that all those that return true precede all those that return false. Returns the number of true elements found.

fn is_partitioned<P>(self, predicate: P) -> bool where
    P: FnMut(Self::Item) -> bool, 

🔬 This is a nightly-only experimental API. (iter_is_partitioned)

new API

Checks if the elements of this iterator are partitioned according to the given predicate, such that all those that return true precede all those that return false.

fn try_fold<B, F, R>(&mut self, init: B, f: F) -> R where
    F: FnMut(B, Self::Item) -> R,
    R: Try<Output = B>, 

An iterator method that applies a function as long as it returns successfully, producing a single, final value.

fn try_for_each<F, R>(&mut self, f: F) -> R where
    F: FnMut(Self::Item) -> R,
    R: Try<Output = ()>, 

An iterator method that applies a fallible function to each item in the iterator, stopping at the first error and returning that error.

fn fold<B, F>(self, init: B, f: F) -> B where
    F: FnMut(B, Self::Item) -> B, 

Folds every element into an accumulator by applying an operation, returning the final result.

fn reduce<F>(self, f: F) -> Option<Self::Item> where
    F: FnMut(Self::Item, Self::Item) -> Self::Item, 

Reduces the elements to a single one, by repeatedly applying a reducing operation.

fn all<F>(&mut self, f: F) -> bool where
    F: FnMut(Self::Item) -> bool, 

Tests if every element of the iterator matches a predicate.

fn any<F>(&mut self, f: F) -> bool where
    F: FnMut(Self::Item) -> bool, 

Tests if any element of the iterator matches a predicate.

fn find<P>(&mut self, predicate: P) -> Option<Self::Item> where
    P: FnMut(&Self::Item) -> bool, 

Searches for an element of an iterator that satisfies a predicate.

fn find_map<B, F>(&mut self, f: F) -> Option<B> where
    F: FnMut(Self::Item) -> Option<B>, 

Applies function to the elements of iterator and returns the first non-none result.

fn try_find<F, R, E>(&mut self, f: F) -> Result<Option<Self::Item>, E> where
    F: FnMut(&Self::Item) -> R,
    R: Try<Output = bool, Residual = Result<Infallible, E>> + Try, 

🔬 This is a nightly-only experimental API. (try_find)

new API

Applies function to the elements of iterator and returns the first true result or the first error.

fn position<P>(&mut self, predicate: P) -> Option<usize> where
    P: FnMut(Self::Item) -> bool, 

Searches for an element in an iterator, returning its index.

fn rposition<P>(&mut self, predicate: P) -> Option<usize> where
    Self: ExactSizeIterator + DoubleEndedIterator,
    P: FnMut(Self::Item) -> bool, 

Searches for an element in an iterator from the right, returning its index.

fn max(self) -> Option<Self::Item> where
    Self::Item: Ord, 

Returns the maximum element of an iterator.

fn min(self) -> Option<Self::Item> where
    Self::Item: Ord, 

Returns the minimum element of an iterator.

fn max_by_key<B, F>(self, f: F) -> Option<Self::Item> where
    F: FnMut(&Self::Item) -> B,
    B: Ord, 

Returns the element that gives the maximum value from the specified function.

fn max_by<F>(self, compare: F) -> Option<Self::Item> where
    F: FnMut(&Self::Item, &Self::Item) -> Ordering, 

Returns the element that gives the maximum value with respect to the specified comparison function.

fn min_by_key<B, F>(self, f: F) -> Option<Self::Item> where
    F: FnMut(&Self::Item) -> B,
    B: Ord, 

Returns the element that gives the minimum value from the specified function.

fn min_by<F>(self, compare: F) -> Option<Self::Item> where
    F: FnMut(&Self::Item, &Self::Item) -> Ordering, 

Returns the element that gives the minimum value with respect to the specified comparison function.

fn rev(self) -> Rev<Self> where
    Self: DoubleEndedIterator, 

Reverses an iterator’s direction.

fn unzip<A, B, FromA, FromB>(self) -> (FromA, FromB) where
    Self: Iterator<Item = (A, B)>,
    FromA: Default + Extend<A>,
    FromB: Default + Extend<B>, 

Converts an iterator of pairs into a pair of containers.

fn copied<'a, T>(self) -> Copied<Self> where
    Self: Iterator<Item = &'a T>,
    T: 'a + Copy, 

Creates an iterator which copies all of its elements.

fn cloned<'a, T>(self) -> Cloned<Self> where
    Self: Iterator<Item = &'a T>,
    T: 'a + Clone, 

Creates an iterator which clones all of its elements.

fn cycle(self) -> Cycle<Self> where
    Self: Clone, 

Repeats an iterator endlessly.

fn sum<S>(self) -> S where
    S: Sum<Self::Item>, 

Sums the elements of an iterator.

fn product<P>(self) -> P where
    P: Product<Self::Item>, 

Iterates over the entire iterator, multiplying all the elements

fn cmp<I>(self, other: I) -> Ordering where
    I: IntoIterator<Item = Self::Item>,
    Self::Item: Ord, 

Lexicographically compares the elements of this Iterator with those of another.

fn cmp_by<I, F>(self, other: I, cmp: F) -> Ordering where
    F: FnMut(Self::Item, <I as IntoIterator>::Item) -> Ordering,
    I: IntoIterator, 

🔬 This is a nightly-only experimental API. (iter_order_by)

Lexicographically compares the elements of this Iterator with those of another with respect to the specified comparison function.

fn partial_cmp<I>(self, other: I) -> Option<Ordering> where
    I: IntoIterator,
    Self::Item: PartialOrd<<I as IntoIterator>::Item>, 

Lexicographically compares the elements of this Iterator with those of another.

fn partial_cmp_by<I, F>(self, other: I, partial_cmp: F) -> Option<Ordering> where
    F: FnMut(Self::Item, <I as IntoIterator>::Item) -> Option<Ordering>,
    I: IntoIterator, 

🔬 This is a nightly-only experimental API. (iter_order_by)

Lexicographically compares the elements of this Iterator with those of another with respect to the specified comparison function.

fn eq<I>(self, other: I) -> bool where
    I: IntoIterator,
    Self::Item: PartialEq<<I as IntoIterator>::Item>, 

Determines if the elements of this Iterator are equal to those of another.

fn eq_by<I, F>(self, other: I, eq: F) -> bool where
    F: FnMut(Self::Item, <I as IntoIterator>::Item) -> bool,
    I: IntoIterator, 

🔬 This is a nightly-only experimental API. (iter_order_by)

Determines if the elements of this Iterator are equal to those of another with respect to the specified equality function.

fn ne<I>(self, other: I) -> bool where
    I: IntoIterator,
    Self::Item: PartialEq<<I as IntoIterator>::Item>, 

Determines if the elements of this Iterator are unequal to those of another.

fn lt<I>(self, other: I) -> bool where
    I: IntoIterator,
    Self::Item: PartialOrd<<I as IntoIterator>::Item>, 

Determines if the elements of this Iterator are lexicographically less than those of another.

fn le<I>(self, other: I) -> bool where
    I: IntoIterator,
    Self::Item: PartialOrd<<I as IntoIterator>::Item>, 

Determines if the elements of this Iterator are lexicographically less or equal to those of another.

fn gt<I>(self, other: I) -> bool where
    I: IntoIterator,
    Self::Item: PartialOrd<<I as IntoIterator>::Item>, 

Determines if the elements of this Iterator are lexicographically greater than those of another.

fn ge<I>(self, other: I) -> bool where
    I: IntoIterator,
    Self::Item: PartialOrd<<I as IntoIterator>::Item>, 

Determines if the elements of this Iterator are lexicographically greater than or equal to those of another.

fn is_sorted(self) -> bool where
    Self::Item: PartialOrd<Self::Item>, 

🔬 This is a nightly-only experimental API. (is_sorted)

new API

Checks if the elements of this iterator are sorted.

fn is_sorted_by<F>(self, compare: F) -> bool where
    F: FnMut(&Self::Item, &Self::Item) -> Option<Ordering>, 

🔬 This is a nightly-only experimental API. (is_sorted)

new API

Checks if the elements of this iterator are sorted using the given comparator function.

fn is_sorted_by_key<F, K>(self, f: F) -> bool where
    F: FnMut(Self::Item) -> K,
    K: PartialOrd<K>, 

🔬 This is a nightly-only experimental API. (is_sorted)

new API

Checks if the elements of this iterator are sorted using the given key extraction function.

impl<'a, T: ?Sized + Ord> Ord for Box<'a, T>

fn cmp(&self, other: &Box<'a, T>) -> Ordering

This method returns an Ordering between self and other.

#[must_use]

fn max(self, other: Self) -> Self

Compares and returns the maximum of two values.

#[must_use]

fn min(self, other: Self) -> Self

Compares and returns the minimum of two values.

#[must_use]

fn clamp(self, min: Self, max: Self) -> Self

Restrict a value to a certain interval.

impl<'a, 'b, T: ?Sized + PartialEq> PartialEq<Box<'b, T>> for Box<'a, T>

fn eq(&self, other: &Box<'b, T>) -> bool

This method tests for self and other values to be equal, and is used by ==.

fn ne(&self, other: &Box<'b, T>) -> bool

This method tests for !=.

impl<'a, 'b, T: ?Sized + PartialOrd> PartialOrd<Box<'b, T>> for Box<'a, T>

fn partial_cmp(&self, other: &Box<'b, T>) -> Option<Ordering>

This method returns an ordering between self and other values if one exists.

fn lt(&self, other: &Box<'b, T>) -> bool

This method tests less than (for self and other) and is used by the < operator.

fn le(&self, other: &Box<'b, T>) -> bool

This method tests less than or equal to (for self and other) and is used by the <= operator.

fn ge(&self, other: &Box<'b, T>) -> bool

This method tests greater than or equal to (for self and other) and is used by the >= operator.

fn gt(&self, other: &Box<'b, T>) -> bool

This method tests greater than (for self and other) and is used by the > operator.

impl<'a, T: ?Sized> Pointer for Box<'a, T>

fn fmt(&self, f: &mut Formatter<'_>) -> Result

Formats the value using the given formatter.

impl<'a, T> TryFrom<Box<'a, [T]>> for Box<'a, [T; 0]>

This impl replaces unsize coersion.

type Error = Box<'a, [T]>

The type returned in the event of a conversion error.

fn try_from(slice: Box<'a, [T]>) -> Result<Box<'a, [T; 0]>, Box<'a, [T]>>

Performs the conversion.

impl<'a, T> TryFrom<Box<'a, [T]>> for Box<'a, [T; 1]>

This impl replaces unsize coersion.

type Error = Box<'a, [T]>

The type returned in the event of a conversion error.

fn try_from(slice: Box<'a, [T]>) -> Result<Box<'a, [T; 1]>, Box<'a, [T]>>

Performs the conversion.

impl<'a, T> TryFrom<Box<'a, [T]>> for Box<'a, [T; 10]>

This impl replaces unsize coersion.

type Error = Box<'a, [T]>

The type returned in the event of a conversion error.

fn try_from(slice: Box<'a, [T]>) -> Result<Box<'a, [T; 10]>, Box<'a, [T]>>

Performs the conversion.

impl<'a, T> TryFrom<Box<'a, [T]>> for Box<'a, [T; 11]>

This impl replaces unsize coersion.

type Error = Box<'a, [T]>

The type returned in the event of a conversion error.

fn try_from(slice: Box<'a, [T]>) -> Result<Box<'a, [T; 11]>, Box<'a, [T]>>

Performs the conversion.

impl<'a, T> TryFrom<Box<'a, [T]>> for Box<'a, [T; 12]>

This impl replaces unsize coersion.

type Error = Box<'a, [T]>

The type returned in the event of a conversion error.

fn try_from(slice: Box<'a, [T]>) -> Result<Box<'a, [T; 12]>, Box<'a, [T]>>

Performs the conversion.

impl<'a, T> TryFrom<Box<'a, [T]>> for Box<'a, [T; 13]>

This impl replaces unsize coersion.

type Error = Box<'a, [T]>

The type returned in the event of a conversion error.

fn try_from(slice: Box<'a, [T]>) -> Result<Box<'a, [T; 13]>, Box<'a, [T]>>

Performs the conversion.

impl<'a, T> TryFrom<Box<'a, [T]>> for Box<'a, [T; 14]>

This impl replaces unsize coersion.

type Error = Box<'a, [T]>

The type returned in the event of a conversion error.

fn try_from(slice: Box<'a, [T]>) -> Result<Box<'a, [T; 14]>, Box<'a, [T]>>

Performs the conversion.

impl<'a, T> TryFrom<Box<'a, [T]>> for Box<'a, [T; 15]>

This impl replaces unsize coersion.

type Error = Box<'a, [T]>

The type returned in the event of a conversion error.

fn try_from(slice: Box<'a, [T]>) -> Result<Box<'a, [T; 15]>, Box<'a, [T]>>

Performs the conversion.

impl<'a, T> TryFrom<Box<'a, [T]>> for Box<'a, [T; 16]>

This impl replaces unsize coersion.

type Error = Box<'a, [T]>

The type returned in the event of a conversion error.

fn try_from(slice: Box<'a, [T]>) -> Result<Box<'a, [T; 16]>, Box<'a, [T]>>

Performs the conversion.

impl<'a, T> TryFrom<Box<'a, [T]>> for Box<'a, [T; 17]>

This impl replaces unsize coersion.

type Error = Box<'a, [T]>

The type returned in the event of a conversion error.

fn try_from(slice: Box<'a, [T]>) -> Result<Box<'a, [T; 17]>, Box<'a, [T]>>

Performs the conversion.

impl<'a, T> TryFrom<Box<'a, [T]>> for Box<'a, [T; 18]>

This impl replaces unsize coersion.

type Error = Box<'a, [T]>

The type returned in the event of a conversion error.

fn try_from(slice: Box<'a, [T]>) -> Result<Box<'a, [T; 18]>, Box<'a, [T]>>

Performs the conversion.

impl<'a, T> TryFrom<Box<'a, [T]>> for Box<'a, [T; 19]>

This impl replaces unsize coersion.

type Error = Box<'a, [T]>

The type returned in the event of a conversion error.

fn try_from(slice: Box<'a, [T]>) -> Result<Box<'a, [T; 19]>, Box<'a, [T]>>

Performs the conversion.

impl<'a, T> TryFrom<Box<'a, [T]>> for Box<'a, [T; 2]>

This impl replaces unsize coersion.

type Error = Box<'a, [T]>

The type returned in the event of a conversion error.

fn try_from(slice: Box<'a, [T]>) -> Result<Box<'a, [T; 2]>, Box<'a, [T]>>

Performs the conversion.

impl<'a, T> TryFrom<Box<'a, [T]>> for Box<'a, [T; 20]>

This impl replaces unsize coersion.

type Error = Box<'a, [T]>

The type returned in the event of a conversion error.

fn try_from(slice: Box<'a, [T]>) -> Result<Box<'a, [T; 20]>, Box<'a, [T]>>

Performs the conversion.

impl<'a, T> TryFrom<Box<'a, [T]>> for Box<'a, [T; 21]>

This impl replaces unsize coersion.

type Error = Box<'a, [T]>

The type returned in the event of a conversion error.

fn try_from(slice: Box<'a, [T]>) -> Result<Box<'a, [T; 21]>, Box<'a, [T]>>

Performs the conversion.

impl<'a, T> TryFrom<Box<'a, [T]>> for Box<'a, [T; 22]>

This impl replaces unsize coersion.

type Error = Box<'a, [T]>

The type returned in the event of a conversion error.

fn try_from(slice: Box<'a, [T]>) -> Result<Box<'a, [T; 22]>, Box<'a, [T]>>

Performs the conversion.

impl<'a, T> TryFrom<Box<'a, [T]>> for Box<'a, [T; 23]>

This impl replaces unsize coersion.

type Error = Box<'a, [T]>

The type returned in the event of a conversion error.

fn try_from(slice: Box<'a, [T]>) -> Result<Box<'a, [T; 23]>, Box<'a, [T]>>

Performs the conversion.

impl<'a, T> TryFrom<Box<'a, [T]>> for Box<'a, [T; 24]>

This impl replaces unsize coersion.

type Error = Box<'a, [T]>

The type returned in the event of a conversion error.

fn try_from(slice: Box<'a, [T]>) -> Result<Box<'a, [T; 24]>, Box<'a, [T]>>

Performs the conversion.

impl<'a, T> TryFrom<Box<'a, [T]>> for Box<'a, [T; 25]>

This impl replaces unsize coersion.

type Error = Box<'a, [T]>

The type returned in the event of a conversion error.

fn try_from(slice: Box<'a, [T]>) -> Result<Box<'a, [T; 25]>, Box<'a, [T]>>

Performs the conversion.

impl<'a, T> TryFrom<Box<'a, [T]>> for Box<'a, [T; 26]>

This impl replaces unsize coersion.

type Error = Box<'a, [T]>

The type returned in the event of a conversion error.

fn try_from(slice: Box<'a, [T]>) -> Result<Box<'a, [T; 26]>, Box<'a, [T]>>

Performs the conversion.

impl<'a, T> TryFrom<Box<'a, [T]>> for Box<'a, [T; 27]>

This impl replaces unsize coersion.

type Error = Box<'a, [T]>

The type returned in the event of a conversion error.

fn try_from(slice: Box<'a, [T]>) -> Result<Box<'a, [T; 27]>, Box<'a, [T]>>

Performs the conversion.

impl<'a, T> TryFrom<Box<'a, [T]>> for Box<'a, [T; 28]>

This impl replaces unsize coersion.

type Error = Box<'a, [T]>

The type returned in the event of a conversion error.

fn try_from(slice: Box<'a, [T]>) -> Result<Box<'a, [T; 28]>, Box<'a, [T]>>

Performs the conversion.

impl<'a, T> TryFrom<Box<'a, [T]>> for Box<'a, [T; 29]>

This impl replaces unsize coersion.

type Error = Box<'a, [T]>

The type returned in the event of a conversion error.

fn try_from(slice: Box<'a, [T]>) -> Result<Box<'a, [T; 29]>, Box<'a, [T]>>

Performs the conversion.

impl<'a, T> TryFrom<Box<'a, [T]>> for Box<'a, [T; 3]>

This impl replaces unsize coersion.

type Error = Box<'a, [T]>

The type returned in the event of a conversion error.

fn try_from(slice: Box<'a, [T]>) -> Result<Box<'a, [T; 3]>, Box<'a, [T]>>

Performs the conversion.

impl<'a, T> TryFrom<Box<'a, [T]>> for Box<'a, [T; 30]>

This impl replaces unsize coersion.

type Error = Box<'a, [T]>

The type returned in the event of a conversion error.

fn try_from(slice: Box<'a, [T]>) -> Result<Box<'a, [T; 30]>, Box<'a, [T]>>

Performs the conversion.

impl<'a, T> TryFrom<Box<'a, [T]>> for Box<'a, [T; 31]>

This impl replaces unsize coersion.

type Error = Box<'a, [T]>

The type returned in the event of a conversion error.

fn try_from(slice: Box<'a, [T]>) -> Result<Box<'a, [T; 31]>, Box<'a, [T]>>

Performs the conversion.

impl<'a, T> TryFrom<Box<'a, [T]>> for Box<'a, [T; 32]>

This impl replaces unsize coersion.

type Error = Box<'a, [T]>

The type returned in the event of a conversion error.

fn try_from(slice: Box<'a, [T]>) -> Result<Box<'a, [T; 32]>, Box<'a, [T]>>

Performs the conversion.

impl<'a, T> TryFrom<Box<'a, [T]>> for Box<'a, [T; 4]>

This impl replaces unsize coersion.

type Error = Box<'a, [T]>

The type returned in the event of a conversion error.

fn try_from(slice: Box<'a, [T]>) -> Result<Box<'a, [T; 4]>, Box<'a, [T]>>

Performs the conversion.

impl<'a, T> TryFrom<Box<'a, [T]>> for Box<'a, [T; 5]>

This impl replaces unsize coersion.

type Error = Box<'a, [T]>

The type returned in the event of a conversion error.

fn try_from(slice: Box<'a, [T]>) -> Result<Box<'a, [T; 5]>, Box<'a, [T]>>

Performs the conversion.

impl<'a, T> TryFrom<Box<'a, [T]>> for Box<'a, [T; 6]>

This impl replaces unsize coersion.

type Error = Box<'a, [T]>

The type returned in the event of a conversion error.

fn try_from(slice: Box<'a, [T]>) -> Result<Box<'a, [T; 6]>, Box<'a, [T]>>

Performs the conversion.

impl<'a, T> TryFrom<Box<'a, [T]>> for Box<'a, [T; 7]>

This impl replaces unsize coersion.

type Error = Box<'a, [T]>

The type returned in the event of a conversion error.

fn try_from(slice: Box<'a, [T]>) -> Result<Box<'a, [T; 7]>, Box<'a, [T]>>

Performs the conversion.

impl<'a, T> TryFrom<Box<'a, [T]>> for Box<'a, [T; 8]>

This impl replaces unsize coersion.

type Error = Box<'a, [T]>

The type returned in the event of a conversion error.

fn try_from(slice: Box<'a, [T]>) -> Result<Box<'a, [T; 8]>, Box<'a, [T]>>

Performs the conversion.

impl<'a, T> TryFrom<Box<'a, [T]>> for Box<'a, [T; 9]>

This impl replaces unsize coersion.

type Error = Box<'a, [T]>

The type returned in the event of a conversion error.

fn try_from(slice: Box<'a, [T]>) -> Result<Box<'a, [T; 9]>, Box<'a, [T]>>

Performs the conversion.

impl<'a, T: ?Sized + Eq> Eq for Box<'a, T>

impl<'a, I: FusedIterator + ?Sized> FusedIterator for Box<'a, I>

impl<'a, T: ?Sized> Unpin for Box<'a, T>